# Performance

* Previously when an array was expanded in the Tree View widget, all
  of the display calculations for were done before the next
  redraw. Now the keys are sorted (as before) but the display
  calculations are made for a maximum of 1000 rows. When more rows are
  needed due to scrolling, another 1000 are calculated at that
  point.

  This provides a near-continuous scrolling experience for arrays with
  large numbers of keys, and ties the expense of expanding an array to
  that of sorting its keys.

# [18693] Prevent long delays when expanding arrays with many keys
